Measurement of the Average Activation Cross Section for the Reaction ⁶³Cu(n, α)⁶⁰Co in the Spontaneous Fission Neutron Field of Californium-252

The average cross section for the reaction ⁶³Cu(n, α)⁶⁰Co has been measured absolutely in the ²⁵²Cf spontaneous fission neutron field by activation in compensated flux geometry with an accuracy of ∼2.4% (1α). A near-point source of ²⁵²Cf and a light mass source-detector assembly in a low-scattering environment was used. The resulting cross-section value was compared with calculated values obtained by convoluting the spectral distribution of ²⁵²Cf neutrons with existing energy-differential data for the reaction ⁶³Cu(n, α)⁶⁰Co. There is very good agreement (within 5%) between the experimental and the calculated average cross section if the results from a recent measurement of the ⁶³Cu(n, α)⁶⁰Co excitation function are used. Thus the reaction ⁶³Cu(n, α)⁶⁰Co, which is an important threshold reaction in reactor dosimetry, fulfills the conditions for a Category I neutron-dosimetry reaction for fission reactor applications.